A. Field of the Invention
The field of the present invention relates generally to vehicle wheel chocks used to prevent movement of a vehicle by releasably engaging one or more wheels of the vehicle. More particularly, the present invention relates to such wheel chocks that are configured for use with tandem wheeled vehicles, such as recreational vehicles, trucks, trailers or the like by frictionally engaging facing tire surfaces of adjacent wheels. Even more particularly, the present invention relates to such wheel chocks that utilize one or more horizontally displaceable wedged block members to prevent movement of the vehicle.
B. Background
Wheel chocks are apparatuses that are configured to generally engage one or more wheels of a vehicle to prevent movement of the vehicle after it has been placed in a parked condition. Tandem wheeled vehicles, such as recreational vehicles, trailers and larger trucks, have tandem axles and wheels which place pairs of adjacent wheels on each side of the vehicle that are spaced generally close to each other, typically two to twelve inches apart at the closest position of the pneumatic tire portion of the wheels. Most wheel chocks for these vehicles are configured to engage both of the adjacent wheels. With regard to recreational vehicles specifically, most of these types of vehicles have tandem wheels. It is commonly known that many people utilize recreational vehicles for camping, attending sporting events or other activities that generally result in the vehicle being placed in a parked condition and being used while parked. For purposes of this disclosure, recreational vehicles include those vehicles that are motorized, meaning they have a gasoline, diesel or other type of motor that drives the vehicle from one location to another, and those that must be towed behind another vehicle, such as a car or truck. Generally, when recreational vehicles are to be parked for any extended period of time, a wheel locking device is utilized to stabilize the vehicle so as to prevent undesirable and/or unauthorized movement of the vehicle. Without stabilization, the movement of persons inside the parked recreational vehicle will typically result in undesirable movement, such as a slight rocking motion, of the vehicle itself. If the vehicle is not parked on substantially level ground, it will tend to roll from its parked position. As a result, the use of wheel chocks to stabilize or immobilize a recreational vehicle is generally considered a necessity instead of a mere convenience. In addition to use for stabilization purposes, wheel chocks are also commonly utilized to prevent theft or other unauthorized movement of a vehicle.
Numerous different types of configurations of wheel chocks are commonly known in the prior art. Generally, all such apparatuses are configured to frictionally engage one or more tire surfaces (i.e., facing tire surfaces for tandem wheeled vehicles) to prevent movement of the vehicle by inhibiting rotation of the tire or tires. Perhaps the most common are those type that have one or more wedge members which are configured to be securely disposed between the supporting surface, such as the ground, paved surfaces, concrete driveways and the like, and the pneumatic tires of the vehicle's wheels. A basic configuration for this type of wheel chock is a single wedge-shaped member that both engages the vehicle's tire and the supporting surface. Some of these have wedges and supporting surface contact sides that are shaped and/or configured to improve the engagement with the tire or the supporting surface. Examples of such apparatuses are shown in U.S. Pat. No. 4,186,823 to White, Jr., U.S. Pat. No. 3,993,167 to Reed, U.S. Pat. No. 2,954,101 to Corson and U.S. Pat. No. 2,797,774 to Eckhart. Some wedge-shaped wheel chocks have a lever or handle mechanism that is configured to improve the engagement of the wheel chock with the tire and supporting surface. Examples of such apparatuses are shown in U.S. Pat. No. 6,390,245 to Metz and U.S. Pat. No. 5,137,121 to Leonard. Although the typical single block wedge only prevents movement of the vehicle in one direction, thereby requiring two such blocks to prevent both forward and backward movement of the vehicle, U.S. Pat. No. 4,582,176 to Roberts discloses a single wedge-shaped apparatus that is configured for use with dual or tandem wheeled trucks. Several prior art patents disclose wheel chocks for tandem wheeled vehicles that are configured with a pair of chock members that are interconnected by a pivoting arm member that the user steps on to force the arm downward and drive the chock members into engagement with the adjacent tires to prevent rotation thereof. Examples of such apparatuses are shown in U.S. Pat. No. 3,845,844 to Woerner and U.S. Pat. No. 3,700,077 to Harder.
Other wheel chocks utilize an operating mechanism which positions the wedge member or members tightly against the tires and in engaging relation with the supporting surface. With regard to tandem wheeled vehicles, these type of wheel chocks generally are configured to engage both tires of a set of adjacent wheels by positioning one wedge-shaped member at each tire in a manner that prevents both wheels from rotating. Typically, the user of the wheel chock places the apparatus between the adjacent tires and operates the mechanism to displace the opposing wedge-shaped members away from each other and into engagement with the adjacent tires. Examples of this type of wheel chock, namely the horizontally displaceable wedge-shaped block member type of wheel chock, are shown in U.S. Pat. No. 4,828,076 to Fox and U.S. Pat. No. 3,695,394 to Carpenter. The Fox patent describes a lock chock for tandem axle vehicles that utilizes a wing nut mounted on a threaded shaft that is turned to extend or retract a pair of blocks into or out of engagement with the adjacent tires. The Carpenter patent describes a locking wheel chock for tandem wheeled vehicles that requires the user to turn a nut in a turnbuckle to extend or retract a pair of block members into or out of engagement with the adjacent tires. A number of patents describe wheel chock apparatuses that have a pair of block members with a vertically disposed operating mechanism to move the blocks into or out of engagement with the tires from above and below the tires, as opposed to horizontally along the supporting surface. Examples of these apparatuses are disclosed in U.S. Pat. No. 5,158,158 to Balogh et. al and U.S. Pat. No. 4,694,936 to Jackson. A number of wheel chock apparatuses utilize separate pairs of engagement members above and below the tires to engage the tires and prevent movement thereof. Examples of these apparatuses are disclosed in U.S. Pat. No. 5,490,582 to Trowbridge, U.S. Pat. No. 4,934,489 to Jackson and U.S. Pat. No. 5,392,880 to Christian. U.S. Pat. No. 5,381,680 to Rauch, Jr. discloses a retractable wheel lock assembly which utilizes a single wedge-shaped member that engages a pair of adjacent wheels from above.
In general, the prior art devices tend to be too cumbersome and/or technically complicated for frequent use by the typical or average recreational vehicle owner or user or even those persons who drive trucks and/or haul trailers for a living. Another common problem with most of the prior art devices is the difficulty the user has is disengaging the chock locking apparatus from between the pair of wheels with which it was engaged. Besides often requiring a significant amount of brute force, many of the prior art apparatuses require the user to get in an awkward or uncomfortable position to disengage the apparatus from between the pair of wheels. As a result, despite the known safety and stabilizing benefits of wheel chocks, very often the user of the vehicle chooses not to utilize the wheel lock apparatuses. This is particularly true for those who are considered part time or weekend recreational vehicle users. Yet another limitation of many presently available wheel chocks is the inability of the apparatus to compensate for narrower or wider spacing between the adjacent tires of a tandem wheeled vehicle. Because of this problem, the manufacturer is required to somewhat narrowly select his or her market for the wheel chock or make a number of different sized wheel chocks to accommodate the differently configured vehicles. Naturally, this increase the manufacturer's cost and creates various inventory issues for the manufacturer and retailer or other supplier.
In order for a wheel chock for tandem wheeled vehicles to be effective, the wheel chock must have a mechanism that moves one or more block members into and out of frictional engagement with adjacent tires with sufficient force that the wheel chock will prevent movement of the vehicle. However, to be useable by the typical recreational vehicle user and others, the wheel chock must also be relatively simple and easy to operate, without requiring any substantial amount of force by the user or requiring him or her to get into an awkward position to engage or disengage the wheel chock. As such, what is needed is a wheel chock that has a mechanical linkage system which simply and easily, but effectively, locks one or more blocking members into and out of frictional engagement with the adjacent tires of a tandem wheeled vehicle. Preferably, an improved wheel chock avoids the use a threaded member or other screw device that are generally known to be time consuming, difficult to operate and require the user to get down to engage or disengage. In addition, a preferred wheel chock apparatus will avoid the use the compound lever systems that are known to be mechanically complex and tend to require excessive force to engage or disengage from the adjacent tires. A preferred wheel chock will prevent the known problem of the block members being essentially stuck between the tire and supporting surface, thereby requiring a generally uncomfortable amount of force or effort to disengage the block member from its locked position. The preferred wheel chock will also accommodate a wide variety of tandem wheel configurations, including a relatively wide range of spacing between adjacent wheels of the vehicle.